Preheat the oven to 356°F (180°C) and lightly grease a 10-inch tart pan with a removable base (or springform pan or pie dish).
Place almonds, walnuts, and oats in a blender or food processor and process into a coarse flour. Then add the dates, syrup, and liquid coconut oil, and process until the mixture sticks together. (If it seems too dry, add a little bit of water or non-dairy milk).
Transfer the mixture into your prepared pan. Press it down firmly and up the sides to create an even tart shell. Bake in the preheated oven for about 15 minutes (or just place in the fridge for a no-bake option).
Allow to cool completely before adding the filling.
Place all ingredients for the lemon filling in a saucepan and whisk to combine (make sure the agar and cornstarch have completely dissolved). Bring to the boil, stirring constantly, then reduce the heat and simmer for another 1-2 minutes, until it has thickened slightly.
Pour the mixture into the tart shell and allow to cool for about an hour at room temperature. Then transfer to the fridge and cool another at least 3 hours (or better overnight), until the filling has set.
Garnish with fresh strawberries and lemon slices over serve with whipped coconut cream.
Enjoy!